Auditorium

ABSTRACT

An auditorium has a domed roof formed by a first part spherical portion covering, without intermediate support, most of an amphitheatre accommodating an audience, and a second part spherical portion covering a stage adjacent the amphitheatre, the first portion being supported only at its periphery, and the second portion consisting of segmental leaves which can open about a common pivot supported by the first portion to uncover the stage, the common pivot being at a vertical axis of the second portion of the roof and above the amphitheatre and the vertical axis of the first portion being above the stage. Wall panels behind the stage can be moved apart to open the rear of the stage to the exterior.

This invention relates to auditoriums of the amphitheatre type as usedfor concerts, theatrical, cinematograph and other public presentations.

A problem in the presentation of such performances is that, where theyare presented in different cities, available facilities may vary greatlyin physical layout and capacity. This may require modification of theperformance or alter the artistic impression provided. The availablefacilities may be ill suited to the size of the expected audience, andusually do not combine facilities for all-season usage with thepotential for an outdoor ambience.

An object of the invention is to provide an amphitheatre type auditoriumproviding standardized but widely adaptable facilities, suitable forall-season, all weather use, and capable of providing the ambience of anoutdoor performance.

It has previously been proposed to provide auditoriums of this typehaving roof portions in the form of rotatable segmental leaves over astage area, as shown for example in British Published Patent ApplicationNo. 2225360A, particularly FIGS. 13 to 15 showing prior art structures.All such structures have required a central pillar, which is highlyundesirable if an audience is to have an unobstructed view of the stage.

According to the invention, there is provided an auditorium, comprisingan amphitheatre having a seating area only partially surrounding astage, a first fixed roof structure covering a majority of theamphitheatre area except for a segmental area above the stage, andsecond movable roof structure of segmental form movable between a firstposition in which it closes said segmental area, and a second positionlapping the first roof structure and leaving said segmental area open,said movable roof structure comprising segmental leaves rotatable inopposite directions about a common pivotal axis between a first closedposition in which the leaves abut and a second open position in whichthey underlay the fixed roof structure, the first and second roofstructures both being part-spherical shells, characterized in that thefixed roof structure is supported only at its periphery, and the movableroof structure is supported at its periphery and by a connection to thefixed roof structure on said common pivotal axis, in that a verticalaxis of a first virtual sphere containing the shell forming the fixedroof structure passes through the stage, and in that a vertical axis ofa second virtual sphere containing the shell forming the movable roofstructure coincides with said common pivotal axis and is locatedhorizontally spaced from the stage so as to intersect the seating areaof the amphitheatre, intermediate between the vertical axis of the firstvirtual sphere and the periphery of the fixed roof structure. Theauditorium may include means to partition off, by radially and/orcirumferentially extending partitions, portions of seating area toprovide amphitheatres of different capacities. Retractable panelsforming a curtain wall may be provided behind that portion of the stagenot surrounded by the seating area.

The above arrangement provides an all weather auditorium of flexiblecapacity which nevertheless is capable of providing an open-air ambienceunder suitable weather conditions.

Further features of the invention will become apparent from thefollowing description of a presently preferred embodiment of theinvention with reference to the accompanying drawings in which:

FIG. 1 is an elevation of the auditorium in accordance with theinvention, facing the amphitheatre, with its roof closed and the wallbehind its stage in place;

FIG. 2 is an end elevation of the auditorium;

FIG. 3 is a vertical cross-section through the stage and amphitheatre;

FIG. 4 is a plan view of the auditorium;

FIG. 5 is a plan view of a lower seating level in the auditorium; and

FIG. 6 is a plan view of an upper gallery seating level in theauditorium.

The auditorium shown in the drawings comprises the following principalcomponents; a banked amphitheatre comprising a seating area having amain seating level 2 and a superposed gallery level 4, a stage 6, afixed main roof 8, an opening auxiliary roof 10, a retractable curtainwall 12 behind the stage, and a foundation 14 supporting theamphitheatre, and curtain wall, supports 16 for the roofs, auxiliarystructures 18 providing services such as restaurants, and service towers20.

The main, fixed roof 8 comprises a part spherical shell supported solelyat an approximately semicircular periphery 21, a virtual spherecontaining the shell having a vertical spherical axis 7 above the stage6, although that portion of the fixed roof above the stage issegmentally cut away along margins 22 converging at an axis 24, wellspaced from the stage and over the seating area of the amphitheatre.Sloped transitional portions 26 extend between the margins 22 and lines28 which extend from the axis 24 towards the ends of the periphery 21.The roof 8 is supported at its periphery by the amphitheatre structureand by the service towers 20 which provide housings for mechanical andother services for the building and elevators 30, as well as support fortelecommunications equipment 32.

The opening auxiliary roof 10 comprises two part-spherical segmentalleaves 34 pivotally connected at their apices for rotation about theaxis 24, which is the vertical axis of a virtual sphere containing theleaves, between a first, closed, position (see FIGS. 1 and 2 and thesolid line depiction in FIG. 4) closing the segmental cutaway in themain roof defined by the margins 22 and a retracted position (see thebroken line depiction in FIG. 4). The leaves 34 are supported at theirouter peripheries by a track 36 carried by the supports 16 behind thestage 6. Since the greater portion of the roof structure is comprised byspherical shells, it can be constructed in modular fashion from ribcomponents of only two different radii, thus simplifying construction.By situating the axis 24 which forms the common pivot point for themovable leaves 34 above the seating on level 2 and substantially spacedfrom the vertical axis of the shell forming the main roof 6 on thecentre line of the amphitheatre a self-supporting structure can beprovided, requiring no central pillar, and in which retraction of theleaves 34 will place the stage 6 in the open air and provide asubstantial open air illusion to the auditorium as a whole, which can begreatly enhanced by withdrawing, into pockets 38, sliding panels 40forming a curtain wall behind the stage 6. Deployment of the panels 40and closing of the leaves 34 provides a wholly enclosed auditoriumduring inclement weather or to provide an enclosed environment. Thelower surfaces of the leaves 34 may support baffles or reflectors foracoustic control purposes, as may the main roof structure 8, as shown at42. A frame 43 may be supported above the stage to support lighting andother equipment.

In order to accommodate different anticipated audience sizes, ordifferent types of presentation, the internal configuration of theseating provided by the auditorium may be adjusted. For example,assuming total seating capacity of the auditorium as shown to be about14000, movable partitions or curtain walls may be provided to reduce theseating capacity of the auditorium. Thus the gallery seating level mayor may not be used, or circumferential partitions may be used to makeavailable only lower portions such as 44 and 46 of the main seatinglevel 2. Alternatively, radial partitions may be utilized to shut offwing portions of the auditorium. Advantageously, such an arrangement canbe utilized to isolate central segments 48 of the gallery seating (seeFIG. 6), with a screen being deployed, for example lowered and rotatedfrom the structure 42 to a position to provide super wide screen cinemapresentations.

We claim:
 1. An auditorium, comprising an amphitheatre having a seatingarea only partially surrounding a stage, a first fixed roof structurecovering a majority of the amphitheatre except for a segmental areaabove the stage, and second movable roof structure of segmental formmovable between a first position in which it closes said segmental area,and a second position lapping the first roof structure and leaving saidsegmental area open, said movable roof structure comprising segmentalleaves rotatable in opposite directions about a common pivotal axisbetween said first closed position in which the leaves abut and saidsecond open position in which they underlay the fixed room structure,the first and second roof structures both being part-spherical shells,characterized in that the fixed roof structure is supported only at itsperiphery, and the movable roof structure is supported at its peripheryand by a connection to the fixed roof structure on said common pivotalaxis, in that a vertical axis of a first virtual sphere containing theshell forming the fixed roof structure passes through the stage, and inthat a vertical axis of a second virtual sphere containing the shellforming the movable roof structure coincides with said common pivotalaxis and is located horizontally spaced from the stage and passesthrough the seating area of the amphitheatre, intermediate between theaxis of the first virtual sphere and the periphery of the fixed roofstructure.
 2. An auditorium according to claim 1, characterized in thata retractable curtain wall is provided behind that portion of the stagenot surrounded by the seating area.